ABSTRACT
Objective To determine the anatomic distribution of metastatic inguinal nodes in gynecological malignancies,and to explore the delineation of clinical target volume(CTV). Methods A retrospective study was performed among 34 patients with gynecological malignancies and inguinal lymph node metastases. According to the anatomic distribution of metastatic inguinal nodes, CTV covering more than 95% of inguinal lymph nodes and the relationship of inguinal nodes with the femoral vein, greater saphenous vein and its branches, superficial fascia, and deep fascia were analyzed using vascular enhancement images obtained by computed tomography and magnetic resonance imaging as well as 3D reconstruction using the Eclipse Planning System. Results The 34 patients had a total of 145 positive inguinal nodes. In the 131 superficial nodes below the inguinal ligament, 129 were located between the superficial fascia and the deep fascia;the upper group of superficial nodes,containing 25 nodes,was located at 1 cm above the public symphysis and along superficial iliac circumflex vein;the middle group,containing 85 superficial nodes and 11 patients with single superficial node metastasis,was located at the same level of the public symphysis and close to the junction of the saphenous vein and the femoral vein;the lower group, containing 21 superficial nodes,was beneath the public symphysis and along the greater saphenous vein and medial and lateral superficial femoral veins.The 14 deep nodes were located on the medial side of the femoral vein. There were no positive nodes on the posterolateral side of the link between the posterolateral edge of the femoral vein and medial edge of the sartorius muscle. The upper edge of CTV kept 142 lymph nodes beneath the upper edge of the superior pubis ramus and left 3 lymph nodes up to the upper edge of the femoral head. The lower edge of CTV kept 143 lymph nodes above the lower edge of the lesser trochanter and left 2 lymph nodes at 2 cm beneath the lower edge of the lesser trochanter. Conclusions For CTV covering 98% of positive inguinal nodes, the anterior edge is the superficial fascia;the medial edge is composed by the inguinal ligament and the border of medial muscle to the femoral vessels;the posterolateral edge is the link between the posterolateral edge of the femoral vein and the medial edge of the sartorius muscle;the upper edge is the upper border of the femoral head;the lower edge is the lower border of the lesser trochanter.